ASTM_D_1729_-_22.pdf

Designation:D172922Standard Practice forVisual Appraisal of Colors and Color Differences ofDiffusely-Illuminated Opaque Materials1This standard is issued under the fixed designation D1729;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the U.S.Department of Defense.INTRODUCTIONThe colors of materials depend on the geometric and spectral nature of the illuminating and viewingconditions.This practice specifies standard conditions for appraising the colors and color differencesof opaque specimens that are diffusely illuminated.Daylight,the natural illuminant,is usually ofprimary interest,but natural daylight is highly variable and is not available at night or in interiorrooms,so simulated daylight is generally used.Colors may match under a light source with onespectral power distribution,but not under another,so the match is usually confirmed under anothervery different source.An incandescent lamp of low correlated color temperature has long been usedto detect mismatches likely to appear under yellower phases of daylight or incandescent light.Industrial color matchers often verify the match with the kind of light likely to be found where theproduct is sold or used.Judgments should be made by observers with superior color vision as ratedwith the FM-100 Hue Test.Even so,there may be substantial individual differences in judgments.1.Scope1.1 This practice specifies the equipment and procedures forvisual appraisal of the colors and color differences of opaquematerials that are diffusely illuminated.These specificationsare of critical importance in color matching.This practicerequires judgments by observers with a minimum of normalcolor vision and preferably superior as rated with the FM-100Hue Test as specified in Guide E1499.1.2 Critical visual appraisal of colors and color differencesof materials such as metallic and pearlescent paints requiresillumination that is nearly a geometric simulation of directsunlight,because such directional illumination permits obser-vation of the sparkle(glitter)and goniochromatism that char-acterize such materials.Such viewing conditions are beyondthe scope of this practice.1.3 The values stated in SI units are to be regarded as thestandard.The values given in parentheses are for informationonly.1.4 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.1.5 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D523 Test Method for Specular GlossD1535 Practice for Specifying Color by the Munsell SystemD4086 Practice for Visual Evaluation of Metamerism1This practice is under the jurisdiction of ASTM Committee E12 on Color andAppearance and is the direct responsibility of Subcommittee E12.11 on VisualMethods.Current edition approved June 1,2022.Published June 2022.Originallyapproved in 1960.Last previous edition approved in 2016 as D1729 16.DOI:10.1520/D1729-22.This standard has been approved for use by agencies of the Department ofDefense to replace Method 4249.1 of Federal Test Method Standard No 141.Consult the DoD Index of Specifications and Standards for the specific year of issuewhich has been adopted by the Department of Defense.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.1D5531 Guide for Preparation,Maintenance,and Distributionof Physical Product Standards for Color and GeometricAppearance of CoatingsE284 Terminology of AppearanceE308 Practice for Computing the Colors of Objects by Usingthe CIE SystemE1164 Practice for Obtaining Spectrometric Data for Object-Color EvaluationE1499 Guide for Selection,Evaluation,and Training ofObservers2.2 ISO/CIE Standa